Question: $ {10.5 \div 2.1 = ?} $
Answer: ${2}$ ${1}$ ${1}$ ${0}$ ${5}$ $\text{Shift the decimal 1 to the right.}$ ${.}$ ${.}$ $\text{How many times does }21\text{ go into }{105}\text{?}$ ${5}$ ${1}$ ${0}$ ${5}$ $-$ ${0}$ ${105}\div21={5}\text{ with a remainder of }{0}$ $\text{The remainder is 0, so we have our answer.}$ $ {10.5 \div 2.1 = 5} $